Drug interactionDrug interactions occur when a drug's mechanism of action is affected by the concomitant administration of substances such as foods, beverages, or other drugs. The cause is often inhibition of, or less effective action, of the specific receptors available to the drug. This influences drug molecules to bind to secondary targets, which may result in an array of unwanted side-effects. The term selectivity describes a drug’s ability to target a single receptor, rendering a predictable physiological response.
Enzyme inhibitorAn enzyme inhibitor is a molecule that binds to an enzyme and blocks its activity. Enzymes are proteins that speed up chemical reactions necessary for life, in which substrate molecules are converted into products. An enzyme facilitates a specific chemical reaction by binding the substrate to its active site, a specialized area on the enzyme that accelerates the most difficult step of the reaction.
Prohibition of drugsThe prohibition of drugs through sumptuary legislation or religious law is a common means of attempting to prevent the recreational use of certain intoxicating substances. While some drugs are illegal to possess, many governments regulate the manufacture, distribution, marketing, sale, and use of certain drugs, for instance through a prescription system. For example, amphetamines may be legal to possess if a doctor has prescribed them; otherwise, possession or sale of the drug is typically a criminal offense.
Mechanism of actionIn pharmacology, the term mechanism of action (MOA) refers to the specific biochemical interaction through which a drug substance produces its pharmacological effect. A mechanism of action usually includes mention of the specific molecular targets to which the drug binds, such as an enzyme or receptor. Receptor sites have specific affinities for drugs based on the chemical structure of the drug, as well as the specific action that occurs there.
Drug classA drug class is a group of medications and other compounds that have similar chemical structures, the same mechanism of action (i.e. binding to the same biological target), similar modes of action, and/or are used to treat the similar diseases. In several dominant drug classification systems, these four types of classifications form a hierarchy. For example, the fibrates are a chemical class of drugs (amphipathic carboxylic acids) that share the same mechanism of action (PPAR agonist) and mode of action (reducing blood triglycerides), and that are used to prevent and treat the same disease (atherosclerosis).